What is the inheritance hierarchy for the UIButton class?

UIButton inherits from UIControl, which in turn inherits from UIView. UIView inherits from UIResponder, and that from NSObject.

The hierarchy looks like this:

NSObject -> UIResponder --> UIView ---> UIControl ----> UIButton

// Example of a base class
// NSObject - the root class
class NSObject {}

// UIResponder - class that defines the interface for event handling
class UIResponder: NSObject {}

// UIView - base class for all views in UIKit
class UIView: UIResponder {}

// UIControl - abstract base class for views that interact with the user
class UIControl: UIView {}

// UIButton - concrete subclass of UIControl for buttons
class UIButton: UIControl {}